Terrain
Terrain is an actor that allows to create natural-like terrains in the level. It's not possible to achieve the same effect with BSP and while it's possible to use static mesh for this terrain actor has its own advantages.
bAllowRigidBodyUnderneath=true
Resources
Terrain Editor User Guide on UDN beta
UE3 Terrain tutorial by Hourences
page revision: 4, last edited: 09 Apr 2008 17:03